High tibial osteotomy guide

ABSTRACT

A cutting block for use in a bone osteotomy procedure is disclosed, and includes a first cutting guide surface, a second cutting guide surface, and a third cutting guide surface. The first, second, and third cutting guide surfaces are adapted to be temporarily affixed to a bone having a first side and a second side such that the first cutting guide surface is disposed on the first side of the bone, and such that the second cutting guide surface and third cutting guide surface are disposed on the second side of the bone forming an angle therebetween.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is an continuation of U.S. application Ser. No.14/012,286, filed on Aug. 28, 2013, which is a divisional of U.S.application Ser. No. 11/480,648, filed on Jul. 3, 2006, which is acontinuation of U.S. application Ser. No. 11/478,788, filed on Jun. 30,2006, and U.S. application Ser. No. 11/478,790, filed Jun. 30, 2006, thedisclosures of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

High tibial osteotomy (“HTO”) procedures have become well-establishedmeans of treating unicompartmental degenerative arthritis of the knee.This condition occurs due to uneven weight bearing of the femoralcondyles on either medial or lateral joint compartments of the tibia.Such uneven weight bearing results from either a varus or valgus defectin the tibia. A varus or valgus defect occurs when the mechanical axisof the knee joint shifts either medially (valgus) or laterally (varus)of the preferred location therefor. It is generally accepted that thepreferred location for the mechanical axis of the knee is at 62% of thetibial plateau from medial to lateral. The process for determining thelocation of the mechanical axis is known in the art. A varus deformitygenerally results in increased loading on the medial joint compartment,while a valgus defect results in increased loading on the lateral jointcompartment. A high-tibial osteotomy procedure uses one of varioustechniques to bring the knee into proper mechanical alignment bycorrecting a deformity therein, whether varus or valgus. As used hereinwhen referring to bones or other parts of the body, the term “proximal”means close to the heart and the term “distal” means more distant fromthe heart. The term “inferior” means toward the feet and the term“superior” means toward the head. The term “anterior” means toward thefront part or the face and the term “posterior” means toward the back ofthe body. The term “medial” means toward the midline of the body and theterm “lateral” means away from the midline of the body.

One existing high-tibial osteotomy procedure is what is known as aclosing-wedge osteotomy. In such a procedure, a wedge of bone is removedfrom the tibia and the opening left by the removal is forced closed andsecured. The wedge is appropriately shaped to correspond to theappropriate amount of angular correction necessary to bring the kneejoint into proper alignment. The procedures for determining both theamount of angular correction and the appropriate wedge shape are knownin the art. Generally speaking, however, the wedge is usually shaped soas to span almost the entire medial-lateral width of the tibia, leavingonly a narrow “hinge” section of bone on the closed end of the wedge.Once the bone wedge is resected, the opening is forced closed and istypically held in such a position using a staple or other similardevice, including bone screws and/or plates. Such procedures are shownin U.S. Pat. No. 5,980,526 to Johnson, et al.; U.S. Pat. No. 6,796,986to Duffner; U.S. Pat. 5,911,724 to Wehrli; U.S. Pat. No. 5,053,039 toHoffman, et al.; U.S. Pat. No. 5,540,695 to Levy, and; U.S. Pat. No.5,601,565 to Huebner.

The closing-wedge HTO procedure has several drawbacks. In particular,the approach (when used to correct a varus deformity) requires atransverse cut to be made from the lateral cortex of the tibia across tonear the medial cortex thereof through a moderately sized lateralincision. Since the base length of the wedge spans the entire tibialmedial-lateral width, the amount of distance to be closed is quitesignificant, resulting in shortening of the tibia, which may requirecorresponding shortening of the fibula. It is problematic to shorten thelength of the tibia because this can lead to problems in the gait of thepatient leading to back, hip or other joint problems, and can complicateany subsequent total knee replacement (“TKR”) procedure which may benecessary. Further, if shortening of the tibia requires that the fibulabe shortened, the HTO procedure is further complicated and patient painand recovery time are increased. Additionally, tibial shortening leadsto a significant amount of soft tissue laxity of the lateralcompartment, which includes the joint capsule, lateral collateralligament, etc. Other complications arise from a closing wedge HTOprocedure because the resected tibial plateau is “hinged” medially, forexample. This can result in the resected joint being extremely unstableduring healing. Subsequent TKR is further complicated by the presence ofthe staple used to secure the joint during healing because the staplemay have to be removed prior to TKR.

An alternative procedure is the opening wedge HTO. In this procedure, asingle cut is made from, for example, the medial cortex of the tibiaacross to near the lateral cortex in order to correct a varus defect (tocorrect a valgus defect a cut is made from the lateral cortex to nearthe medial cortex). As with closing wedge HTO, the cut in an openingwedge HTO procedure extends through almost the entire tibia, leavingonly enough bone on the lateral tibia to form a hinge section. The cutis then forced open to form a wedge having an angle corresponding to therequired amount of angular correction. This procedure can also be usedto correct a valgus defect, with the cut originating on the lateraltibia, extending through the tibia to near the lateral tibia. Once thecut is opened, an appropriately shaped wedge can be inserted into thecut to support the tibial plateau at the desired angle. The wedge can bemade of a known bone-substitute material, an autograft taken from thepatient's iliac crest or an allograft taken from a donor. The wedge isthen secured in place using hardware typically in the form of boneplates and screws.

Various disadvantages to the opening wedge HTO exist as well.Specifically, the amount of the distance to be “opened” can be quitesignificant, leading to lengthening of the leg and an undesirable amountof soft tissue tensioning of, for example, the medial compartment, whichincludes the joint capsule, the medial collateral ligament, etc.Furthermore, the lateral or medial hinging of the osteotomy makes itextremely unstable, due to the amount of leverage applied to the hingesection from the opposite side of the tibia. This instability makes theknee unable to resist torsional loads applied to the joint. Therefore,it is necessary to secure the cut with bulky plates and/or screws inorder to stabilize the joint while it heals. The presence of suchhardware can complicate any subsequent TKR procedure which may berequired. Additionally, due to the large size of the wedge inserted intothe cut, resorption and incorporation of a bone substitute device thatmay be used to fill the wedge is lengthy. While it is preferred that thewedge be made from autograft material, which is usually removed from theiliac crest of the patient. This harvesting requires a separateprocedure to be performed to harvest the autograft, which adds time,pain, blood loss and the risk of infection to the procedure. Thereforevarious allograft implants have been designed to fill the wedge asillustrated in U.S. Pat. No. 6,575,982 to Bonutti, and in U.S. Pat. Pub.No. 2005/0075641 to Singhatat, et al. These implants generally are madeof a biologically compactable material and may include features topromote affixation to the bone and/or bony ingrowth. Alternatively, thewedge can be left unfilled, the tibial plateau being supported by plateor bracket such as those shown in U.S. Pat. No. 6,823,871 to Schmiedingand U.S. Pat. Pub. No. 2003/0195516 to Sterett.

Various tools have been developed in order to facilitate both theopening and closing wedge osteotomy procedure. Typically, these includecutting guide surfaces which are capable of being affixed to the boneand provide a surface which is used to guide a bone saw or other knowninstrument into proper alignment for the desired cut or cuts. Typically,these guides are designed to affix to either the medial or lateral sideof the tibia, depending on the type of correction required and theprocedure used. By taking either a medial or lateral approach forcutting, the patellar tendon is easily avoided; however, theseapproaches make alignment of cuts more difficult, because the mechanicalaxis is not visible from the side of the knee.

A further alternative procedure known in the art is a dome tibialosteotomy. In this procedure, the entire proximal tibia, as well as theproximal fibula are detached from the remaining tibia using a curved ordome-shaped bone cut. The proximal tibia is then repositioned in thecorrect alignment and secured in place with various forms of hardware,which can include staples, plates, screws, or cerclage wire. The totalbisection of both the proximal tibia and fibula leads to an extremelyunstable joint, which requires a great deal of hardware forstabilization, which would, most likely, need to be removed prior tosubsequent TKR. This procedure is advantageous because it neithershortens nor lengthens the leg to a problematic extent. However, it isgenerally regarded as too invasive or risky for practical purposes.

SUMMARY OF THE INVENTION

The present invention relates to a cutting block for use in a boneosteotomy procedure. The cutting block includes a first cutting guidesurface, a second cutting guide surface, and a third cutting guidesurface. The first, second, and third cutting guide surfaces of thecutting block are adapted to be temporarily affixed to a bone having afirst side and a second side such that the first cutting guide surfaceis disposed on the first side of the bone, and such that the secondcutting guide surface and third cutting guide surface are disposed onthe second side of the bone forming an intersecting angle therebetween.

The first and second cutting guide surfaces of the cutting block may bedisposed on a first arm of the cutting block, and the third cuttingguide surface disposed on a second arm of the cutting block. In such anarrangement, the second arm is preferably rotatably affixed to the firstarm. The first cutting guide surface and the second cutting guidesurface are preferably disposed on the first arm in a parallelrelationship to each other such that the first cutting guide surface islocated proximally of the second cutting guide surface. In such anembodiment, the first cutting guide surface is used to form a first cutin the proximal tibia, the second cutting guide surface is used to forma second cut in the proximal tibia, and third cutting guide surface isused to form a third cut in the proximal tibia. Each of these cuts has aterminal end, and the terminal ends of the first and second cuts form anoverlap therebetween.

An alternative embodiment of the present invention relates to a cuttingblock for use in a high-tibial osteotomy procedure. The cutting block ispreferably adapted to be temporarily affixed to an anterior portion of aproximal tibia having a first side and a second side. The first andsecond sides may be either the lateral or medial sides of the tibia. Thecutting block includes a body having a first cutting guide surface and areceiving portion formed therein. Preferably, the first cutting guidesurface is disposed substantially on the first side of the proximaltibia. The cutting block further includes first and secondinterchangeable portions, which are adapted to be selectively insertedwithin the receiving portion of the body. A second cutting guide surfaceis positioned in the first interchangeable portion such that when thefirst interchangeable portion is inserted within the receiving portion,the second cutting guide surface is disposed substantially on the secondside of the proximal tibia and is parallel to the first cutting guidesurface. A third cutting guide surface is positioned within the secondinterchangeable portion such that when the second interchangeableportion is inserted within the receiving portion, the third cuttingguide surface is disposed substantially on the second side of theproximal tibia and forms an obtuse angle relative to the first cuttingguide surface.

A further embodiment of the present invention relates to a system forperforming a bone osteotomy procedure. The system includes a firstcutting block having a first cutting guide surface formed therein. Thefirst cutting block is being adapted to be affixed to the bone in afirst position such that the cutting guide surface is disposedsubstantially on a first side of the bone and a second position suchthat the first cutting guide surface is disposed substantially on asecond side of the bone and is located distally of the first position.The system further includes a second cutting block having a secondcutting guide surface formed therein and being adapted for affixation tothe bone such that the second cutting guide surface is positionedrelative to the first position of the first cutting guide surface suchthat it forms an intersecting angle therewith.

A still further embodiment of the present invention relates to a systemfor performing a high-tibial osteotomy procedure. The system includes afirst cutting block having a first cutting guide surface formed therein.The first cutting block is adapted to be affixed to an anterior surfaceof a proximal portion of the tibia in a first position such that thecutting guide surface is disposed substantially on a first side of thetibia and a second position such that the first cutting guide surface isdisposed substantially on a second side of the tibia and is locateddistally of the first position. The system further includes a secondcutting block having a second cutting guide surface formed therein. Thesecond cutting block is adapted for affixation to the anterior surfaceof the proximal portion of the tibia such that the second cutting guidesurface is positioned relative to the first position of the firstcutting guide surface such that it forms an intersecting angletherewith.

An embodiment of the present invention further includes a method forperforming an osteotomy procedure on a bone having a first side and asecond side. The method includes making a first cut in the boneextending in a first direction from an outside surface on the first sideof the bone to a first line being disposed within the bone and extendingin a second direction orthogonal to the first direction substantiallythrough the bone. The method also includes making a second cut in thebone extending in a first direction from an outside surface on thesecond side of the bone to a second line being disposed within the boneand extending in a second direction orthogonal to the first directionsubstantially through the bone. The second cut is spaced apart from thefirst cut along a longitudinal axis of the bone. The method furtherincludes making a third cut in the bone extending in a first directionfrom an outside surface on the first side of the bone to a third linenear being disposed within the bone and extending in a second directionorthogonal to the first direction substantially through the bone. Thefirst cut and third cut form an intersecting angle therebetween alongthe respective first directions thereof such that an apex is formedalong a the third line.

A further embodiment of the present invention includes a method forperforming a high tibial osteotomy. The method includes making a firstcut in a proximal tibia in a first plane, and making a second cut in aproximal tibia in a second plane. The first and second planes are spacedin a proximal-distal direction. The method further includes making athird cut in the proximal tibia in a third plane. The third plane is atan angle with and intersecting one of said first and second planes. Thefirst, second and third cuts open to a medial or lateral side of theproximal tibia. The method also includes removing a bone wedge formed bythe intersection of the third cut with one of the first or second cuts.Additionally, the method includes closing a wedge shaped opening formedby the removal of the bone wedge by rotating the proximal tibia about ananterior to posterior axis to open the one of the first and second cutsnot intersecting with the third cut. The method further includesinserting the bone wedge into one of the first and second bone cutsopened by the rotation about the anterior-posterior axis.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood on reading the followingdetailed description of nonlimiting embodiments thereof, and onexamining the accompanying drawings, in which:

FIG. 1 is an anterior view of a proximal tibia during a step of aprocedure showing three bone cuts according to an embodiment of thepresent invention;

FIG. 2 is an anterior view of a proximal tibia showing removal of a bonewedge made by two of the cuts of FIG. 1;

FIG. 3 is an anterior view of a proximal tibia during a step of aprocedure showing the insertion of the bone wedge of FIG. 2 in the thirdcut of FIG. 1;

FIG. 4 is an anterior view of a proximal tibia after insertion of thebone wedge of FIG. 3;

FIG. 5 is an isometric view of a filler implant for insertion into areaof the tibia from which the bone wedge has been removed, as seen inFIGS. 2-4;

FIG. 6 is an anterior view of a proximal tibia during a step of aprocedure showing three bone cuts according to a second embodiment ofthe present invention;

FIG. 7 is an anterior view of a proximal tibia showing the bone wedgemade in FIG. 6 moved from one side to the other;

FIG. 8 is an isometric view of a first embodiment of a cutting blockaccording to an embodiment of the present invention showing a removableinsert;

FIG. 9 is an isometric view of the insert for the cutting block of FIG.8;

FIG. 10 is an isometric view of an alternative insert for use with thecutting block of FIG. 8;

FIG. 11 is an isometric view of an osteotome according to an embodimentof the present invention;

FIG. 12 is an isometric view of a tibia with the cutting block of FIG. 8mounted thereto during step in a process according to an embodiment ofthe present invention;

FIG. 13 is an isometric view of a tibia with the cutting block of FIG. 8mounted thereto and the osteotome of FIG. 11 inserted therein to form afirst cut during step in a process according to an embodiment of thepresent invention;

FIG. 14 is an isometric view of a tibia with the cutting block of FIG. 8mounted thereto during step in a process according to an embodiment ofthe present invention;

FIG. 15 is an isometric view of a tibia as shown in FIG. 14 with theosteotome of FIG. 11 used to finalize a second cut in the tibia;

FIG. 16 is an isometric view of a tibia with the cutting block of FIG. 9mounted thereto including the insert of FIG. 10 during step in a processaccording to an embodiment of the present invention;

FIG. 17 is an isometric view of a tibia as shown in FIG. 16 with theosteotome of FIG. 11 inserted therein to finalize the second cut in thetibia;

FIG. 18 is an isometric view of a tibia during step in a process showingthe removal of the bone wedge prior to insertion of a filler implant;

FIG. 19a is an anterior view of a tibia with a second embodiment of thecutting block mounted thereon in a first arrangement;

FIG. 19b is an anterior view of a tibia with a the embodiment of thecutting block shown in FIG. 19 mounted on the tibia in a secondarrangement;

FIG. 20 is a top view of a tibia as shown in FIG. 19;

FIG. 21 an isometric view of a tibia with the second embodiment of thecutting block mounted thereon and a saw blade being used to make a firstcut;

FIG. 22 is an isometric view of a tibia with a first cutting block of asystem according to a further embodiment of the present inventionattached thereto in a first position;

FIG. 23 is an isometric view of a tibia with the cutting block shown inFIG. 22 attached thereto in a second position;

FIG. 24 is a front view of a tibia with a second cutting block from thesystem of the present embodiment attached thereto;

FIG. 25 is an isometric view of the second cutting block shown in FIG.24;

FIG. 26 is an anterior view of a proximal tibia during a step of aprocedure showing three bone cuts according to an embodiment of thepresent invention; and

FIG. 27 is an anterior view of a proximal tibia during a step of aprocedure showing rotation of the tibial head to close the openingcreated after removal of a bone wedge therefrom.

DETAILED DESCRIPTION

In describing the preferred embodiments of the subject matterillustrated and to be described with respect to the drawings, specificterminology will be resorted to for the sake of clarity. However, theinvention is not intended to be limited to the specific terms soselected, and it is to be understood that each specific term includesall technical equivalents which operate in a similar manner toaccomplish a similar purpose.

Referring to the drawings, wherein like reference numerals representlike elements, there is shown in FIGS. 1-4, in accordance with oneembodiment of the present invention, an anterior view of the right tibia10 with a series of cuts which can be used to complete an HTO procedure.The illustration in FIG. 1 shows exemplary locations for cuts in an HTOprocedure used to correct a varus defect on the proximal tibia 11;however, as would be understood by one having reasonable skill in theart upon reading this disclosure, the procedure of the present inventioncan also be used to correct a valgus defect. As shown in FIG. 1, firstcut 12 extends in the medial-lateral direction from the medial cortex ofthe tibia toward the centerline of the tibia. Preferably, first cut 12extends in the medial-lateral direction to a terminus that is lateral ofthe centerline of the tibia. First cut 12 extends in theanterior-posterior direction from the anterior tibial cortex through theposterior cortex. Second cut 14 extends in the medial-lateral directionfrom the lateral cortex toward the centerline of the tibia. Preferably,second cut 14 extends to a terminus that is medial of the centerline ofthe tibia such that overlap 22 is formed between first cut 12 and secondcut 14. Preferably, first and second cuts 12, 14 are perpendicular tothe mechanical axis of the tibia. Additionally, second cut 14 ispreferably proximal to first cut 12. Third cut 16 extends in themedial-lateral direction from the lateral cortex of the tibia toward thecenterline of the tibia at an angle relative to second cut 14 so as toform autograft 18, having a wedge shape, therebetween. The angle abetween third cut 16 and the second cut 14 corresponds with the amountof angular correction determined to be necessary for the knee. Aspreviously stated, the procedure of the current invention can be used tocorrect either a varus or valgus defect in the tibia. The location andplacement of first, second and third cuts 12, 14, 16 will vary dependingon which of these defects is being treated. For example, FIG. 1 shows avarus defect on the right tibia which is treated by forming second andthird cuts 14, 16 on the lateral side of the proximal tibia 11.Conversely, if a valgus defect is treated, second and third cuts 14, 16are formed on the medial side of proximal tibia 11, and first cut 12 isformed on the lateral side thereof. As shown in FIG. 1, the procedure ofthe present embodiment is particularly useful in treating a varus defectwherein second cut 14 is located proximal of the fibular head 24, whichmay prevent the need for a distraction thereof during the procedure.When making reference to first, second and third cuts 12, 14, 16throughout this disclosure, it is noted that the ordinal reference ismade only for convenience and relates only to a preferred order in whichcuts are made in accordance with one embodiment of the presentinvention. While it is preferred that first, second and third cuts 12,14, 16 are made in order of reference, it is to be understood thatfirst, second and third cuts can be made in any order.

In a preferred method for performing an HTO procedure according to anembodiment of the present invention, first cut 12 is made in tibia 10,followed by second cut 14 and third cut 16, respectively. As shown inFIG. 2, once first, second and third cuts 12, 14, 16 have been made,autograft 18 is removed from tibia 10 to form closing wedge 26. Then,the tibial plateau 11 is rotated so as to close closing wedge 26 whileexpanding first cut 12 to form open wedge 13, as shown in FIG. 3.Preferably, as shown in FIG. 2, filler implant 28 is inserted intoclosing wedge 26 prior to rotation of the tibial head 11.

A filler implant 28 is shown in FIG. 5; the preferred filler implant 28is generally planar in shape with a profile designed to generally matchthe profile of the area to which it is inserted. The thickness ofimplant 28 should be such that it can compensate for the materialremoved from the bone due to the cutting of the bone. Depending on thespecific procedure used to make the required cuts in the bone, thethickness of filler implant 28 may need to be either approximately thatof one saw blade or of two saw blades. Furthermore, the preferredimplant 28 has a substantially porous structure comprising a pluralityof openings 29 to allow for bone ingrowth during the healing processafter the procedure. In order to increase stability of the knee jointduring the healing process, implant 28 can further have a surfacedesigned to increase the friction between the interior surfaces of theknee and the surface of the implant 28. This can include having fixationprotrusions 30 extend from implant 28. The insert may be made of metalor a bioabsorbable material such as polylactide-glycolide polymer. Theinsert may be coated with an osteoinductive or osteoconductive materialsuch as hydroxyapatite and/or BMPs such as OP-I.

Referring now to FIG. 4, once opening wedge 13 has been formed from thefirst cut 12, autograft 18 is inserted into opening wedge 13 to therebyprovide the required amount of angular correction to form aproperly-oriented plateau 11′ of the tibia 10. The procedure fordetermining the appropriate amount of angular correction in such aprocedure is well-known in the art. Finally, a well-known adjustablestaple or clamping device (not shown) is placed in holes 37, 39 formedboth proximally and distally of closing wedge cuts 14, 16, and acompressive load is applied to the bone to prevent movement thereofwhile healing occurs. Examples of such devices are shown in U.S. Pat.No. 4,913,144 to Del Medico, and U.S. Pat No. 4,852,588 to Outerbridge.

FIGS. 6 and 7 depict an alternative arrangement for first, second andthird cuts 112, 114, 116 as used in correction for a varus defect intibia 110. A method for performing an HTO procedure according to thisembodiment of the present invention includes making first cut 112 in thetibia 10 near the proximal end 11 thereof so as to extend in themedial-lateral direction from the lateral cortex of the tibia toward thecenterline thereof. Second cut 114 is then formed in tibia 10 proximalof first cut 112 extending in the medial-lateral direction from thelateral cortex toward the centerline of the tibia 10. Preferably, bothfirst cut 112 and second cut 114 extend medially of the centerline ofthe tibia 110. Second cut 114 is formed at an angle relative to firstcut 112 and extends to intersect first cut 112 so as to form a removablewedge-shaped autograft 118 therebetween. Third cut 116 is formed intibia 110 preferably proximally of second cut 114 extending in themedial-lateral direction from the medial cortex of tibia 110 toward thecenterline of tibia 110. Preferably, third cut 116 extends to a terminusthat is lateral of the centerline of tibia 110 so as to form an overlap122 between first cut 112 and third cut 116. The distance between thirdcut 116 and second cut 114 in the proximal direction should beappropriate for overlap portion 122 to form a hinge between tibial head111 and the remaining portion of the tibia 110. Autograft 118 isextracted from tibia 110 to form closing wedge 119. The tibial head 11is then rotated to close closing wedge 119 and open opening wedge 121from third cut 116. Autograft 118 is then inserted into opening wedge121. The resected joint is then secured using staples or clamps asdiscussed with respect to FIGS. 1-4. As previously discussed, FIGS. 6-7depict a pattern for first second and third cuts 112, 114, 116 used tocorrect a varus deformity in the knee; however, it is understood thatthe method of the present embodiment can be used to correct a valgusdeformity by forming first and second cuts 112, 114 in tibia 110 so asto originate on the medial side of tibia 110, and to form third cut 116so as to originate on the lateral side of tibia 110. This embodiment ofthe present invention is particularly useful when correcting a valgusdefect because it allows for opening wedge 12 to be positioned proximalof the fibular head 24. As discussed with reference to FIGS. 1-5,implant 28 can be inserted into closing wedge 119 prior to rotation ofthe tibial head. Implant 28 is structured to compensate for the loss ofbone material due to the thickness of the cutting instrument used information of the cuts and to provide stability for the joint duringhealing.

Referring now to FIG. 8, an embodiment of a cutting block that can beused to aid in forming first, second and third cuts 12, 14, 16 for anHTO procedure according to an embodiment of the present invention isshown. In describing preferred embodiments of the cutting block of thepresent invention, reference will be made to directional nomenclatureused in describing the human body. It is noted that this nomenclature isused only for convenience and that it is not intended to be limitingwith respect to the scope or structure of the invention. When referringto specific directions, the device is understood to be described onlywith respect to its orientation and position during an exemplaryapplication to human body.

As shown in FIG. 8, a preferred cutting block 200 according to oneembodiment of the present invention includes body 202 which has a firstguide surface 204 formed therein. The particular embodiment of cuttingblock 200 shown in FIG. 8 is preferably used to form the cutting patternshown in FIGS. 1-4, but it would be understood by one of reasonableskill in the art upon reading this disclosure that cutting block 200shown in FIG. 8 could be modified to form other arrangements for cuttingpatterns used in HTO procedures according to alternative embodiments ofthe present invention. Returning now to FIG. 8, in the exemplaryembodiment illustrated, cutting block 200 is adapted to be affixed tothe anterior portion of the proximal tibia, first guide surface 204being positioned on the medial side of body 202. First guide surface 204is preferably adapted to form first cut 12 (FIG. 1). Body 202 furtherincludes a receiving portion 205, which is adapted to receive a firstcutting guide insert 206 (FIG. 9) or second insert 216 (FIG. 10)therein. First insert 206 is preferably used to form second cut 14according to the method of the present invention discussed withreference to FIGS. 1-4. Accordingly, first insert 206 has second guidesurface 208 formed therein such that when first insert 206 is insertedinto receiving portion 205, second guide surface 208 is substantiallyparallel to first guide surface 204 and located proximally thereto. Inthe preferred embodiment, the guide surfaces are in the form slotsformed in body 202. In preferred embodiment, insert 206 includes flange210 formed in the outer periphery of the lower portion thereof so as tocorrespond with a groove 211 formed around the outer periphery ofreceiving portion 205. Second insert 216 is preferably adapted to beused in forming third cut 16, as described with reference to FIGS. 1-4.Accordingly, second insert 216 has third guide surface 218 formedtherein such that when second insert 216 is engaged within receivingportion 205 third guide surface 218 is appropriately angled andpositioned relative to first guide surface 204 to form third cut 16.Second guide 216 is adapted for engagement within receiving portion 205in a similar fashion as with respect to first insert 206.

Cutting block 200 is formed of a material sufficient to give cuttingblock 200 an appropriate rigidity to accurately guide a cuttinginstrument for formation of the cuts necessary for the HTO procedure.Preferably, cutting block 200 is made from a material that allows formultiple uses, which includes the ability to be repeatedly subjected tothe various sterilization procedures used in the art. Acceptablematerials for cutting block 200 include, but are not limited to,surgical steel, titanium or other similar materials.

As shown in FIGS. 11-18, a further embodiment of the present inventionincludes a method for performing an HTO procedure according to aparticular embodiment of the present invention using cutting block 200.This method includes forming an incision near the knee of the patientsuitable for introduction of cutting block 202 to the anterior proximaltibia. In an alternative embodiment of the present invention, twoincisions can be made in the knee area of the patient, one lateral ofthe patella tendon and one medial of the patella tendon. The incision isthen retracted and body 202 of cutting block 200 is introduced to theproximal portion tibia 10. Body 202 of cutting block 200 is thenpositioned such that the lateral plane 240 (FIGS. 8, 11-13) of insertportion 205 is preferably just proximal to the fibular head 24 (shown inFIG. 1). An alignment rod 244 is then placed into alignment rod hole 242which is affixed to body 202 of the cutting block 200. Alignment rod 244is used to align cutting block 200 with the mechanical axis of thetibia, which is typically in the varus-valgus and flexion-extensionabout the distal end of the tibia. Holes are then drilled in proximaltibia using guide holes 236 in body 202. Fixation pins 246 are theninserted into the proximal tibia through guide holes 236 in order tomaintain body 202 in the appropriate position on tibia 210. Oncealignment and fixation are achieved, alignment rod 244 is then removedfrom hole 242.

When using an anterior approach to the proximal tibia in performing anosteotomy procedure according to the current embodiment of the presentinvention, while a saw blade can be used to start cuts 12, 14,interference with the patella tendon of the patient prevents a straightbone saw as it is known in the art from being used to complete cuts 12,14 of an appropriate width for completion of the procedure. Accordingly,an osteotome 250 as shown in FIG. 12, having generally an L-shapedcutting portion, is used in this procedure. Osteotome 250 has a bodyportion 252 and a cutting portion 254 structured such that body portion252 extends through cutting guide surface and allows cutting portion 254to reach behind the patella tendon so that the necessary cuts can becompleted, as shown in FIG. 13. Preferably, osteotome has a guide arm256 that provides further support for cutting portion 254 and furthermates with guide holes 258 formed in body 202 of cutting block 200.Guide arm 256 is preferably affixed to body portion 252 using screw 257.When such an ostetome is used, the method according to the currentembodiment of the present invention includes the step of drilling acorresponding guide hole 259 in the proximal tibia using guide hole 258.These holes 259 are shown in FIG. 18. Preferably, osteotome 250 isstructured such that guide holes 259 are formed at the terminal ends offirst, second and third cuts 12, 14, 16. Such an arrangement not onlyprovides for further guidance of osteotome 250 within tibia 10, but alsoreduces the stress concentration within the bone which would be presentat the terminal end of a cut without such a hole. Removal of stressconcentrations is preferred because stress concentrations may lead toformation of cracks within the bone during rotation of the tibial heador during healing.

In the preferred method, first cut 12 is partially formed in theproximal tibia by inserting a saw (not shown) onto cutting guide surface204 and initiating first cut 12 through the anterior cortex andextending directly posteriorly through the posterior cortex of theproximal tibia. Accordingly first, second and third cutting guidesurfaces 204, 208, 218 are partially formed so as to engage the sawblade to be used, as would be understood in the art. First cut 12 isextended as medially and as laterally as possible using the straightbone saw, which includes extending first cut 12 through the medialcortex of the tibia. First cut 12 is then continued by insertingosteotome 250 through first guide surface 204 and maneuvering thecutting portion 254 of the osteotome 250 behind the patella tendon.Guide arm 256 is then extended through guide hole 258 a and is affixedto the cutting portion 254 in the body portion 252 as shown in FIG. 13.Osteotome 250 is then driven, by means known in the art, posteriorlyuntil it penetrates the posterior cortex of the proximal tibia.Osteotome is then disassembled and removed from slot 204 and guide hole258 a. Cut 214 is then formed first by drilling a hole using osteotomeguide hole 258 b through to the posterior cortex of the proximal tibia.Referring now to FIG. 14, insert 206 is then engaged in receivingportion 204 of body 202. Second cut 14 is then formed in a similarfashion to the first cut by first using a straight bone saw andfinishing the cut with L-shaped osteotome 250 using guide hole 258 b tosecure arm 256 (as shown in FIG. 15). Next, both the osteotome and firstinsert 206 are removed from tibia 10.

As shown in FIGS. 16-17, third cut 16 is then formed by first slidinginsert portion 216 into receiving portion 204 of body portion 202. Asdiscussed above, third guide 218 is formed within insert portion 216 soas to be angled relative to first guide 205 of receiving portion 204 soas to provide the appropriate angle for third cut 16 corresponding tothe appropriate amount of angular correction for the knee. In apreferred embodiment of the present invention, a number of differentinsert portions 216 of varying angles can be included in a kit with bodyportion 202 allowing the surgeon to select the appropriate insert whichwill correspond to the predetermined amount of angular correction. Guidehole 258 c is then used to drill a hole 259 c through tibia 10 to theposterior cortex thereof. Third cut 16 is then formed as discussed abovein the same manner as first cut 12 and second cut 14 by initiating thecut with a straight bone saw and finishing the cut with osteotome 250.Third cut 16 may be formed so as to not extend behind the patellatendon; however, it may still be preferred to form third cut usingosteotome 250. At this point all instruments are removed from the knee,including cutting block 200 and the osteotomy is completed as discussedabove.

As shown in FIG. 18, autograft 18 is removed from tibia 10, formingclosing wedge 26, into which implant 28 may be inserted. Preferably,cutting block 200 is formed so as to be used on the anterior portion ofthe proximal tibia, and accordingly will be formed along the posteriorportion 230 so as to match the general profile of the anterior portionof the proximal tibia. Further, as shown in FIG. 8 body 202 includes acutout or recessed area 232 formed in the posteriorily-facing surfacethereof which allows cutting block to straddle the patellar tendon ofthe patient. If necessary, a corresponding cutout of recessed area 234may be formed in first insert 206 and second insert 216.

Referring now to FIGS. 19-21, an alternative cutting block 300 accordingto a further embodiment of the present invention is shown. Although theparticular cutting block 300 shown in FIGS. 19-21 is shown as beingadapted so as to form a pattern for first, second, and third cuts 112,114, 116 as shown in FIG. 6-7, it is to be understood that one havingreasonable skill in the art upon reading this disclosure could adaptsuch a cutting block 300 to perform other variations of the procedureaccording to further embodiments of the present invention, includingthose performed on the opposite knee or to correct a varus, as opposedto valgus, condition. As shown in FIGS. 19a and b, cutting block 300 hasa first arm 302 having a first guide 304 formed therein to be used inmaking first cut 112. Cutting block 300 further includes a second arm306 which is rotatably mounted to first arm 302 at a hinge with pivotpin 311, and includes second guide surface 308 and a third guide surface310 formed therein. Each of second and third guide surfaces 308, 310 arestructured so as to provide a guide for a bone saw used in formingsecond cut 114 and third cut 116, respectively. Second guide surface 308and third guide surface 310 are arranged on second arm 306 to as to besubstantially parallel to each other. Further, third guide surface 310is positioned within second arm 306 so as to be proximal to second guide308. Second and third guides 308, 310 are preferably positioned onopposites sides of second arm 306 in the medial-lateral direction so asto correspond to the preferred locations of second and third cuts 114,116.

The rotational affixation of second arm 306 to first arm 302 about pivotpin allows for an infinite number of positions to be chosen in order toprovide the desired angular correction for an HTO procedure accordingthe embodiments of the present invention. Cutting block 300 is adaptedto be affixed to the anterior portion of the proximal tibia, andaccordingly includes a profile 312 that substantially matches that of atypical anterior proximal tibia. Cutting block 300 is further adapted tobe used on the anterior portion of proximal tibia by incorporation ofcutout 314 therein. As with cutout 232 of FIG. 8, cutout 314 isstructured so as to allow cutting block 302 to straddle the patellatendon of the patient. Fixation of cutting block to the tibia isachieved by inserting fixation pins (not shown) into holes 315, 316which are formed in cutting block 302.

A further aspect of the present invention includes a method forperforming a high tibial osteotomy (HTO) procedure according to anembodiment of the present invention using cutting block 300. To beginthe procedure, an incision is made near the knee of the patient to allowaccess to the anterior portion of the proximal tibia. Preferably asingle cut is made, but optionally two cuts can be made, one mediallyand one laterally of patella tendon 340. Once access is gained to theproximal tibia, cutting block 300 is introduced to the tibia 10 throughthe incision and placed adjacent to the anterior proximal tibia suchthat cut out 314 straddles patella tendon 340 of the patient. First arm302 of cutting block 300 is then aligned, preferably with first cuttingguide surface 304 substantially parallel to the mechanical axis of thetibia, and secured to the tibia using a fixation pin inserted throughhole 315 and into tibia 110 (as shown in FIG. 19a ). Second arm 306 isthen rotated about hinge 311 such that the angle between first cuttingguide surface 304 and second guide 308 corresponds to the amount ofangular correction required for the procedure (as shown in FIG. 19b ).Second arm 306 is then affixed to the proximal tibia by inserting afixation pin through hole 316 and into tibia 10.

Next, first cut 112 is made in the proximal tibia by initiating the cutwith a straight bone saw with the aid of first guide 304. Interferencewith patella tendon of the patient may prevent first cut 312 from beingmade at the appropriate medial-lateral width with respect to the tibiausing a straight bone saw. Accordingly, in order to make first cut 112of the desired width, first cut 112 is finished using an osteotome asshown in FIG. 21. Osteotome 318 is shown as being generally L-shaped,having an elongated body portion 320 and a cutting portion 322 extendingapproximately perpendicular thereto. First cut 312 is completed usingosteotome 318 by extending osteotome onto first guide surface 304 andmanipulating end portion 322 around and behind patella tendon 340 of thepatient. To ensure that first cut 112 is made at the appropriate width,osteotome 318 is formed having a guide arm 324 therein so as tosubstantially mate with guide slot 326 formed in cutting guide surface304. When osteotome 318 is inserted into cutting guide surface 304 guidearm 324 is engaged with guide slot 326. Osteotome 318 is then advancedinto the proximal tibia and through the posterior cortex thereof.Osteotome 318 is then removed from the width 110.

Second cut 314 and third cut 316 are formed in a similar fashion as withrespect to first cut 312 by initiating the cut with a straight bone sawand finishing the cut with osteotome 318. Once the desired cuts havebeen made, cutting block 300 and fixation pins are removed from the kneeand the surgery is completed as discussed above with reference to FIGS.6 and 7.

FIGS. 19-25 show an alternative embodiment of a cutting block systemthat can be used in completing an HTO procedure according to anembodiment of the present invention. In the particular embodimentillustrated, the procedure is one which is carried out to correct avalgus deformity in the proximal portion of a left tibia 410, as shownin FIG. 26. In such a procedure, a cutting pattern similar to that whichis shown in FIG. 27 is made in the proximal tibia 410. This patternincludes a first cut 412, a second cut 414 and a third cut 416 whichproduces a removable, wedge-shaped section 418 of bone that can beremoved from the proximal tibia 410. It is noted that, although ordinaldesignations are given to the cuts described herein as being made in theproximal tibia, such designations are made for convenience only and arenot intended to limit the scope of the invention described herein.

The cutting block system of the current embodiment includes a firstcutting block 500, shown in FIG. 22. First cutting block 500 includes acutting guide portion 502 which includes a first cutting guide surface504 formed therein. Cutting guide surface 504 is generally planar andpreferably (as shown in FIG. 22) includes a top portion 503 and a bottomportion 505 such that it is capable of surrounding a cutting instrument,such as an oscillating saw, osteotome or other similarly suitableinstrument, on both a top side and a bottom side thereof. First cuttingblock 500 also includes arm 506 that extends from the cutting guideportion 502 in a direction that lies along a plane formed by the cuttingguide surface 504. Arm 506 includes a plurality of holes 508 extendingtherethrough in a direction substantially orthogonal thereto.Furthermore, first cutting block 500 includes a sliding member 510 thatis slideably engaged on arm 506. Sliding member 510 includes hole 512formed therein that is substantially parallel to the holes 508 formed inarm 506.

The cutting block system of the present embodiment also includes asecond cutting block 550, which is shown in FIG. 24. Second cuttingblock 550 includes second cutting guide surface 554 which, in theparticular embodiment illustrated in FIG. 24 is shown as having both atop portion 553 and a bottom portion 555, each being substantiallyplanar and open to the other. In this manner, second cutting guidesurface 554 is capable of surrounding a suitable cutting instrument fromboth the top and bottom. Such an arrangement is preferable because itmay improve the accuracy with which the desired cuts are made. Secondcutting block 550 further includes flange 556 which projects fromposterior surface 558 of second cutting block 550. Flange is a generallyplanar structure having an elongate width and depth. Flange 556 isarranged at an angle a with respect to second cutting guide surface 554such that second cutting block 550 can be used to form third cut 416 inproximal tibia 410.

In a method of using this embodiment of the present invention (discussedwith reference to FIGS. 22-27), a first pin 514 and a second pin 516 areinserted into the proximal tibia, preferably by first drilling a holeinto the proximal tibia in the desired location for each pin and then bypress-fitting the pins 514, 516 into the hole. The desired location forfirst pin 514 is preferably along a line directed substantially in theanterior-posterior direction that is located along the desired terminalend 413 of first cut 412 (as shown in FIG. 26). Similarly, second pin516 is inserted into the proximal tibia 410 in a location that ispreferably along a line directed substantially in the anterior-posteriordirection that is located along the desired terminal end 415 of secondcut 414.

Once first 514 and second 516 pins are in place, first cutting block 500is assembled onto pins 514, 516 in the position shown in FIG. 22. Inthis position, first cutting guide surface 504 is positionedsubstantially on the lateral side of the left tibia 410. In thisorientation, the plurality of holes 508 within arm 506 are locatedproximally of hole 512 within sliding member 510. First cutting block500 is assembled in this position onto proximal tibia 410 by firstaligning one of the plurality of holes 508 disposed within arm 506 withfirst pin 514. The hole 508 a aligned with pin 514 is selected so thatproper alignment of first cutting guide surface 504 relative to thelateral side of tibia 410 is achieved. In such an alignment, the closedend 507 of cutting guide surface is located just laterally of patellartendon 432, the contour of cutting guide portion 502 follows as closelyas possible the profile of the tibia 410, and arm 506 is spacedanteriorily apart from patellar tendon 432. Once the proper hole 508 ais selected, it is aligned with first pin 514. Next, hole 512 disposedwithin sliding member 510 is aligned with second pin 516 by movingsliding member 510 along arm 506 to the required location. Oncealignment of holes 508 a, 512 with respect to first pin 514 and secondpin 516 has been completed, first cutting block 500 is slid along pins514, 516 until cutting guide portion 502 contacts a portion of thesurface of proximal tibia 410. Proper alignment of first cutting guidesurface 504 with respect to the desired location of first cut 512 isachieved by spacing apart first pin 514 and second pin 516 from oneanother in the proximal-distal direction by the same distance as that bywhich holes 508 in arm 506 are spaced apart from hole 512 in slidingmember 510 in the same direction. This direction should be equal to thedesired thickness for the bone hinge section 434 (shown in FIGS. 26 and27). Preferably, bone hinge section 434 should be thick enough so as tonot fracture during post-operative recovery, but thin enough so as notto break, particularly in response to an applied torsional load, duringsubsequent rotation of the tibial plateau.

Once first cutting block is properly affixed to proximal tibia 410 inthe proper position, first cut 412 is formed using a cutting instrument,preferably in the form of an oscillating bone saw, in connection withfirst cutting guide surface 504. Preferably, first cut 412 is started bydriving the cutting instrument in a generally posterior direction, withan edge thereof substantially abutted against the closed end 507 offirst cutting guide 504. Because closed end 507 is placed laterally ofthe patellar tendon 434, this procedure allows first cut 412 to bestarted without interference with the patellar tendon 434. Once firstcut 412 is started in this manner, it may be finished by rotating thecutting instrument around and behind the patellar tendon. This rotationis accommodated by the proximally-extending shape of cutting guideportion 502, which allows for the cutting instrument to be manipulatedbehind patellar tendon 434 while maintaining contact with first cuttingguide surface 504. Although, depending on the particular procedure bywhich the cutting block system of the present invention is used, the endof first cut 413 may be blind, the placement of first pin 514 at thedesired location for the end 413 of first cut 412 allows first pin 514to act as a stop for the cutting instrument. That is, the presence offirst pin 514 effectively limits the medial distance to which first cut412 can be made.

Once first cut 412 is completed, first cutting block 500 is removed fromthe proximal tibia 410 by sliding first cutting block 500 in an anteriordirection on pins 514, 516. First cutting block is then rotated into asecond position, as shown in FIG. 23, and re-engaged with pins 514, 516in such a position. The assembly of the first cutting block 500 ontofirst and second pins 514, 516 in this second position is similar to theassembly thereof in the first position. In this manner, one of the holes508 a in arm 506 is properly aligned with second pin 516 and hole 512 insliding member 510 is aligned with first pin 514, then first cuttingblock 500 is slid into contact with the anterior portion of proximaltibia 410. In this position, first cutting guide surface 504 is directedtoward the medial side of the proximal tibia 410, and is aligned in thedesired location for second cut 414. In this position, the fact that theholes 508 in arm 506 are aligned substantially on the plane defined byfirst cutting guide surface 504 serves to align first cutting guidesurface in the proper position for second cut such that second pin 516is located at the terminal end 415 thereof. Once first cutting block 500is appropriately positioned, a cutting instrument is used to form secondcut 414 in a similar manner to that which is described above withrespect to the formation of first cut 412.

Once second cut 414 is formed in the above-described manner, firstcutting block 500 is removed from the proximal tibia 410 by slidingfirst cutting block 500 in a generally anterior direction to disengagepins 514, 516 from holes 508 a, 512. Subsequently, second cutting block550 is introduced and affixed to the proximal tibia 410. This isaccomplished by aligning hole 560 formed in second cutting block 550with second pin 516 and sliding second cutting guide 550 on second pin516 until it comes into engagement with the anterior portion of theproximal tibia 410. As this is done, flange 556 is aligned with andinserted into first cut 412. The insertion of flange 556 into first cut412 serves to properly orient second cutting guide surface 554 at angleα with respect to first cut. Angle α preferably corresponds to apredetermined angle of correction that is desired for the particularbone being operated upon, and may be determined by methods known in theart. Generally, multiple variations of second cutting block 550 can bemade, each having different values for α formed therein. Such variationsof second cutting block 550 can be provided in a kit from which asurgeon performing an operation according to an embodiment of thepresent invention, having determined an appropriate value for α, canselect an appropriate variation of second cutting block 550.

Once second cutting block 550, having an appropriate value for α isassembled onto the proximal tibia 410, third cut 416 is made using acutting instrument, preferably in the form of an oscillating bone saw onsecond cutting guide surface 554. Closed end 557 of second cutting guidesurface 554 is preferably located laterally of the patellar tendon 434when second cutting block 550 is properly affixed to proximal tibia 410.Accordingly, third cut 416 can be made by driving a cutting instrumentin a substantially posterior direction along closed end 557 of secondcutting guide surface 554. Preferably terminal 557 of second cuttingguide surface 554 is located within second cutting block 550 such thatit is positioned within a point along first cut 512. It is furtherpreferred that closed end 557 does not extend distally of first cut 512.After completion of third cut 516, a removable wedge-shaped section 418remains, which is removed from proximal tibia 410. The procedure is thencompleted in a similar manner as that which is described with respect toother embodiments of the present invention.

Although the method of the present embodiment has been discussed withrespect to use of a cutting block, as shown and described with respectto the various figures herein, in completing an HTO procedure to correctfor a varus deformity, it would be understood by one having reasonableskill in the art that a cutting block could be used in an HTO procedurefor correcting a valgus deformity. Further, although the presentinvention has been discussed with respect to an osteotomy procedureperformed on the knee of a patient, and more specifically the proximaltibia of the patient, it would be understood to one having reasonableskill in the art that such procedure can be used in connection withother joints of the human body. Such joints include, but are not limitedto, the elbow and wrist.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims.

The invention claimed is:
 1. A method of performing a bone osteotomyprocedure, the method comprising: affixing a cutting block to a boneportion, the cutting block comprising: a first segment adapted to beaffixed to a bone portion; and a second segment adapted to be affixed tothe bone portion; wherein the first and second segments are pivotablyconnectable together by a pivot portion such that the first and secondsegments are rotatable with respect to one another about a pivot axisextending transverse to a longitudinal axis of the bone portion; whereinthe first and second segments are adapted to be spaced apart from oneanother along the longitudinal axis of the bone portion when the firstand second segments are pivotably connected together and affixed to thebone portion; wherein the second segment includes a first cutting guideand a second cutting guide unitarily formed therein such that the firstand second cutting guides have a fixed angular orientation with respectto one another; and wherein at least one of the first and second cuttingguides is defined by a slot extending lengthwise in a longest directionof the slot, the longest direction of the slot being substantiallyorthogonal to the pivot axis; and forming at least two cuts in the boneportion using the first and second cutting guides to guide a bonecutting apparatus, wherein at least one of the at least two cuts is madeby passing the bone cutting apparatus along the first cutting guide andanother of the at least two cuts is made by passing the bone cuttingapparatus along the second cutting guide.
 2. The method of claim 1,wherein the first and second segments are adapted to be spaced apartfrom one another along the longitudinal axis by the pivot portion. 3.The method of claim 2, wherein the pivot portion includes a pivot pinabout which the first and second segments are rotatable.
 4. The methodof claim 1, wherein the first and second cutting guides are spaced fromone another along the longitudinal axis.
 5. The method of claim 1,wherein the first and second segments are affixable to the bone portionby respective fixation pins.
 6. The method of claim 5, wherein each ofthe first and second segments includes at least one hole for receivingthe respective fixation pins.
 7. The method of claim 1, wherein thefirst and second segments are adapted to abut the bone portion whenaffixed to the bone portion, the first and second segments having acontoured profile to match a profile of the bone portion.
 8. The methodof claim 1, wherein the bone portion is an anterior portion of aproximal portion of a tibia.
 9. The method of claim 1, wherein the firstand second cutting guides are oriented substantially parallel to oneanother.
 10. The method of claim 1, wherein the first and second cuttingguides are positioned on the second segment on opposite sides of thelongitudinal axis from one another.
 11. The method of claim 1, whereinthe first segment includes a third cutting guide surface.
 12. A methodof performing a bone osteotomy procedure, the method comprising:affixing a cutting block to a bone portion, the cutting blockcomprising: a first segment adapted to be affixed to a bone portion; anda second segment adapted to be affixed to the bone portion; wherein thefirst and second segments are pivotably connectable together by a pivotportion such that the first and second segments are rotatable withrespect to one another about a pivot axis extending transverse to alongitudinal axis of the bone portion, the longitudinal axis of the boneportion being aligned with a longest direction of the bone portion;wherein the first and second segments are adapted to be spaced apartfrom one another along the longitudinal axis of the bone portion whenthe first and second segments are pivotably connected together andaffixed to the bone portion; and wherein the second segment includes afirst cutting guide and a second cutting guide formed therein such thatthe first and second cutting guides have a fixed angular orientationwith respect to one another; and forming at least two cuts in the boneportion using the first and second cutting guides to guide a bonecutting apparatus, wherein at least one of the at least two cuts is madeby passing the bone cutting apparatus along the first cutting guide andanother of the at least two cuts is made by passing the bone cuttingapparatus along the second cutting guide.
 13. The method of claim 12,wherein the bone cutting apparatus is a bone saw.
 14. The method ofclaim 12, wherein the bone cutting apparatus is an osteotome.
 15. Themethod of claim 12, wherein at least one of the first and second cuttingguides are defined by a slot in the second segment, the bone cuttingapparatus being guided by the slot by being received within the slot.16. The method of claim 12, further comprising rotating the first andsecond segments with respect to one another about the pivot portion. 17.A method of performing a bone osteotomy procedure, the methodcomprising: affixing a cutting block to a bone portion, the cuttingblock comprising: a first segment; and a monolithic second segmentpivotably connected to the first segment by a pivot portion such thatthe first and second segments are rotatable with respect to one anotherabout a pivot axis, the second segment including a first cutting guideand a second cutting guide formed therein such that the first and secondcutting guides have a fixed angular orientation with respect to oneanother and at least one of the first and second cutting guides isdefined by a slot extending lengthwise in a longest direction of theslot, the longest direction being substantially orthogonal to the pivotaxis; wherein the first and second segments are spaced apart from oneanother by the pivot portion; and forming at least two cuts in the boneportion using the first and second cutting guides to guide a bonecutting apparatus, wherein at least one of the at least two cuts is madeby passing the bone cutting apparatus along the first cutting guide andanother of the at least two cuts is made by passing the bone cuttingapparatus along the second cutting guide.
 18. The method of claim 17,wherein each of the first and second segments includes at least one holefor receiving a respective bone fixation pin.